The contingent valuation method (CVM) is one of the most dominant techniques for estimating the economic value of environmental goods. The willingness to pay (WTP) of respondents depends on their opinions but not the true market behaviors, so there are many uncertainty factors such as insufficient available environment information and different questionnaire formats. These uncertainty factors immediately affect respondents′ WTP. This paper is mainly concerned with contingent value estimation in the presence of response uncertainty. We expand the questionnaire regarding payment card type by adding a question reflecting the degree of certainty respondent′s payment. Then we attempt to build the uncertainty model which is used to estimate the total economic value of protecting the ecological environment along the Baotian highway. The results indicate that using the uncertainty model the average willingness to pay is 32.12 RMB and the total economic value of ecological environment is 2842-3487 thousand RMB. There is a great contrast between 32.12 and 62.17 which is the average willingness to pay without considering uncertainty. Especially the difference of the total economic value arrives at 2939-3266 thousand RMB. This shows that uncertainty has a very large affect on the mean WTP. Not considering uncertainty will lead to imprecise results or a large error.